Percussion-fuse for shells



D. J. CARTWRIGHT.

PERCUSSION FUSE FOR SHELLS.

APPLICATION FILED OCT. 8. 1917.

1,31 1,678. Patented July 29, 1919.

THE COLUMIHA PLANOGRAMI c0 WASHINGTON, n. c.

"cunts s'rnrns PATENT curios;

DAVID J. CARTWRIGHT, 0F ELASTON, PENNSYLVANIA, ASSIGNOR, BY MESNE ASSIGNMENTS, TO LIBERTY ORDNANCE CORPORATION, OF NEW YORK, N. Y.,

A CORPORATIONOF NEW YORK.

PERCUSSION-FUSE Eon SHELL-S.

Specification of Letters Patent. Patented july 29, 19.19

Application filed October 8, 1917. Serial No. 195,265.

To all whom it may concern Be it known thatI, DAVID J. CAn'rwnIeH'r, a citizen of the UnitedStates, and a resident of Easton, in the county of Northampton and State of Pennsylvania, have invented certain new and useful Improvements in Percussion-Fuses for Shells, of which the following is a full, clear, concise, and exact description, such as will enable others skilled in the art to which the invention relates to make and use the same, reference being made therein to the accompanying drawings, which form a part of this specification.

My invention relates to percussion fuses designed for use with shells or projectiles containing a bursting charge, and to cause the explosion ofsuch charge when the shell contacts with the target; and the object thereof is to provide a fuse which will be more simple in construction, more reliable in its action, and one the parts of which may be more cheaply manufactured and more readily assembled than has heretofore been the case in fuses of the general type or class to which my invention relates.

With the above and other objects of invention in view, my invention comprises the improved percussion fuse illustrated in the accompanying drawing, described in the following specification, and particularly claimed, and in such variations and modifications thereof as will be obvious to those skilled in the art to which my invention relates.

In the drawing accompanying and forming a part of this specification and wherein the preferred embodiment of my invention is illustrated, and wherein thesame refer-,

ences numerals are employed, to designate like parts in the several views Figure 1 is aviewshowing a section of my improved fuse upon a central plane extending longitudinally thereof,cthe parts, being shown in the positions which they occopy when the fuse is in its unarmed condition;

Fig. 2 is a similar view showing the position assumed by the parts'during the flight of the shell, and after the said parts have assumed an armed condition; 1

Fig. 3 is a view showing one of the elements of 'my improved fuse by itself and apart from other elements;

Fig. 4 is a view showing a modified form of the element shown in Fig. 3, and;

Figs. Sand 6 are fragmentary views illustrating modified forms of another element of my improved fuse. c

My improved percussion fuse comprises a main body portion 5 in the form of a hollow shell or casing having screw threads upon its exterior surface so that the fuse may be screwed into a threaded opening provided in the rear end or base, or in a like opening in the point of a shell containing a bursting charge, and which casing serves as a support for and contains the various elements and parts of the fuse hereinafter referred to indetail. The forward or inner end of said casing carries a priming charge of explosive material indicated by the reference numeral (3, the same being shown as contained in a cup shaped receptacle 7 having a flangeS; which receptacle is held in place and against a cap supporting member 9 carried by and which closes the inner end of the casing 5, and is provided with a recess or cavlty within which a percussion cap or prlmer 10 of any kind or type so long as it is suitable for the purpose of effecting-the explosion of the shell is located. In the embodiment of my invention illustrated the periphery of the cap supporting member rests upon an annular ledge 12 (a disk 13 having a central opening be ing preferably placed against the inside surface of said cap support and held in place between the support and the ledge, in order to more securely hold the cap 10 in place within the recess or cavity provided for it), and the extremity of the casing is turned inward and made to overlie the flange ,8, as shown at 14, to thereby hold the receptacle containing the priming charge, as well also as the percussion tap support, in place and upon and to the inner orright hand end of the casing 5. The details of construction and arrangement of the cap support and priming charge holding means are not, however, involved in this present invention; and any suitable form and arrangement of cap supporting member and holder for the priming charge, may be employed.

The hollow shell or casing is commonly or hammer located within and movable longitudinally of the casing; but which plunger is not connected in any way with the said casing. The plunger is provided with a 1011- gitudinally extending passage, which passage is enlarged at its inner end whereby an annular ledge 16 is formed; and a space or chamber 17 of greater diameter than the diameter of the passage through the plunger is provided at the inner end of the plunger.

The peripheral wall 18 of the enlarged chamber 17 is quite thin, and extends beyond the ledge 16 and to the right to such an extent that the extremity 19 of the firing pin 20 is kept well away from the percussion cap 10 when the fuse is in the unarmed condition in which it is illustrated in Fig. 1; at which time the inner or right hand end of the plunger or hammer abuts against the percussion cap supporting member 9, or, rather, against the cap retaining disk 13, in the embodiment of my invention illustrated.

Located within the chamber 17 and held in place against the ledge 16 is a combined safety and locking member 21, preferably of disk-like form as best shown in Fig. 3, and having a central opening 22 and a series of radially extending slots 23, whereby a plurality of stops or fingers 24: are pro vided; the disk or locking member being of a material of sufficient stiffness to prevent the inner end 19 of the firing pin 20 from coming into contact with the percussion cap 10 during the handling of the shell and before it is fired from the gun, but of a material which, upon rearward movement of the plunger due to the violent shock to which the shell is subjected when the gun is fired, will yield and permit the fingers 2-1 to be bent and turned into the recess or chamber 17 during which bending operation the said fingers are made to assume the posltiens in which they are shown in Fig. 2 of the draw- The combined safety and locking member 21 is shown as held in place within the chamber orv recess 17, and against the ledge 16, by means of an annular spacing sleeve 25; which sleeve in turn is held in place by turning the extremity of the wall 18 over the end thereof, as shown at 26; although the locking and safety member may be otherwise secured in place and to the plunger or hammer by which it is supported and carried, as will be appreciated.

The firing pin 20 lies within the longitu dinally extending passage of the plunger or hammer 15; and the forward or right hand end thereof abuts against the stops 24 of the safety and locking member 21 when the parts are assembled and in their unarmed condition illustrated in Fig. 1, and before the shell equipped with the fuse is fired from a gun; from which it follows that the extremity or point 19 of the firing pin will be prevented from coming into contact with the percussion cap 10 and accidentally firing the shell during such handling as the shell is ordinarily subjected to, and notwithstanding such shocks as may result in such handling. iVhen however the shell is fired from a gun and starts to move forward at the high velocity communicated to it by the propelling charge of explosive material within the gun, the plunger, being unconnected with and free to move within the interior of the casing 5, as explained, tends to lag relative to the casing, or to remain at rest for a short time, because of its inertia, and because of such tendency it is moved to the left relative to the fuse casing, or is set back therein; or, as otherwise stated, said plunger remains at rest for an instant while the shell and fuse easing move forward independently of the plunger. During this action the firing pin itself moves forward with the casing because of the fact that its rear end abuts a ainst the rear wall or bottom of the chamber within the casing 5, asshown, and, as the plunger is set back or moves relative to the firing pin toward the left (there being sufficient room between the rear end of the plunger and the bottom wall of the chamber to permit th1s movement, as illustrated) the stops 2% of the safety and locking device are carried past the forward end of the firing pin and are bent or turned into the recess or chamber 17 and finally snap into a groove 27 provided adjacent the forward end of the firing pin at the end of the rearward movement of the plunger because of the resilience of the material of which the combined safety and locking member is made; the free ends of the stops partaking of a movement in a direction substantially parallel with the direction of movement of the plunger, and substantially.

parallel with the axis of the firing pin, during this rearward or set back movement of the plunger and the arming of the fuse, as will be appreciated. The firing pin and plunger are now locked together because ofthe engagement of the extremities of the stops 24 with the forward wall 28 of the groove 27, and the parts have assumed the armed position in which they are illustrated in Fig. 2. Subsequently, and when the shell strikes the target, the plunger and firing pin move onward together, because of their momentum, and the extremity 19 of the firing pin strikes and detonates the cap 10, thus firing the detonating charge (3 and, in turn, the main bursting charge of the shell, as will be understood.

The resistance offered by the stops 24 to the movement of the plunger 15 toward the left as it isset back in the casing 5 as hereinbefore explained may obviously be varied by varying the number or form of the said stops, or the form of the end of the firing pin engaging therewith, or in both said ways. Thus Fig. f shows stops 29 narrower than the stops in Fig. 3, from which it follows that the resistance with which they oppose movement of the plunger toward the left will be reduced, and, obviously a greater or less number of the stops than four, the number shown, may be employed.

Again, Fig. 5 shows the end of the firing pin 30 as beveled, as at 31, whereby it will move past the stops more smoothly and readily; while Fig. 6 shows the end of the firing pin 32 as uniformly curved throughout the area which contacts with the stops, as at 33, thus further reducing the resistance offered by the stops to the movement of the plunger toward the left as it is set back in the casing.

From the premises it will be appreciated that the plunger and firing pin are both entirely free from and unconnected with the casing 5 of the fuse, or with one another, as by means of or through a positive mechanical connection or connections, and that said members are in no way locked or otherwise seeured to one another prior to the firing of the shell from the gun; from which it follows that the parts may be readily assembled and at a minimum of expense by simply placing the firing pin within the plunger, and the two within the interior of the fuse casing, and then securing the cap support, and the chamber holding the priming or detonating charge in place upon the inner end of the casing. Furthermore, the arming of the fuse leaves no roughened or sheared surfaces past which the plunger moves in one direction as it is set back, and in a reverse direction when the shell hits the target and is exploded, which surfaces, when present, are liable to interfere with the movements of the firing plunger within the casing and with the proper operation of the shell.

Having thus described and explained my .invention, I claim and desire to secure by Letters Patent- 1. In a percussion fuse, a hollow casing; a cap supporting member carried by said casing; a plunger unconnected with and located within, and movable longitudinally of said casing; a firing pin unconnected with said plunger or casing, and the rear end of which abuts against the end wall of said casing, so that said plunger may move rearward relative to said firing pin; a resilient combined safety and locking member carried by said plunger and adapted to prevent the firing pin from striking a cap carried by said cap supporting member, and to yield in a direction substantially parallel with the direction of movement of said plun ger; and means cooperating with said combined safety and locking member for looking said firing pin and plunger together after said plunger has moved rearwardly, as aforesaid, to thereby arm the fuse.

In a percussion fuse, a hollow casing; a cap supporting member carried by said casing; a vplunger unconnected with and located within, and movable longitudinally of said casing; a firing pin unconnected with said plunger or casing, and the rear end of which abuts against the end wall of said casing, so that said plunger may move rear- 7 ward relative to said firing pin; and a resilient combined safety and locking member carried by said plunger and so located as to engage the forward end of said firing pin, and which member is adapted to prevent the firing pin from striking a cap carried by said cap supporting member when the fuse is in an unarmed condition, and to yield and subsequently positively engage with and lock said firing pin and plunger together after said plunger has moved rearwardly, as aforesaid, to thereby arm the fuse.

3. In a percussion fuse, a hollow casing; a cap supporting member carried by said casing; a plunger located within and movable longitudinally of said casing, and having a longitudinally extending passage; a firing pin located within the passage in said plunger, and the rear end of which engages the end wall of said casing so that said plunger may move rearward relative to said firing pin; a combined safety and locking member carried by said plunger and adapted to engage the forward end of the firing pin and prevent the firing pin from striking a 100 cap carried by said cap supporting member, and to yield in a direction substantially parallel with the axis of the firing pin; and means cooperating with said combined safety and locking member for locking said 105 firing pin and plunger together after said plunger has moved rearwardly, as afore-' said, to thereby arm the fuse.

4. In a percussion fuse, a hollow casing; a cap supporting member carried by said 110 casing; a plunger located within and movable longitudinally of said casing, and having a longitudinally extending passage; a

firing pin located within the passage in said plunger, and the rear end of which engages the end wall of said casing so that said plunger may move rearward relative to said firing pin; and a combined safety and locking member carried by said plunger and adapted to prevent the firing pin from striking a cap carried by said cap supporting member when the fuse is in an unarmed condition, and to yield in a direction substantially parallel with the axis of thefiring pin upon rearward movement of said plunger and to subsequently engage with said firing pin and lock said firing pin and plunger together after said plunger has moved rearwardly, as aforesaid, to thereby arm the fuse.

5. In a percussion fuse, a hollow casing; a

cap supporting member carried by said casing; a plunger located within and mo able longitudinally of said casing, and having a longitudinally extending passage and an en larged chamber; a firing pin located within the passage in said plunger, and the rear end of which engages the end wall of said casing so that said plunger may move rearward relative to said firing pin; a combined safety and locking member carried by said plunger and located within said chamber, and which member is adapted to prevent, the firing pin from striking a cap carried by said cap supporting member when the fuse is in an unarmed condition, and to yield in a direction parallel with the axis of the firing pin upon rearward movement of said plunger; and means carried by said firing pin and engaged by said combined safety and locking member after it has yielded, as aforesaid, for locking said firing pin and plimger together to thereby arm the fuse.

6. In a percussion fuse, a hollow easing; a cap supporting member carried by said casing; a plunger located within and movable longitudinally of said casing, and having a longitudinally extending passage; a firing pin located Within the passage in said plunger; a combined safety and locking member carried by said plunger and located at the forward end thereof and having a yieldable resilient stop adapted to engage the forward end of the firing pin and prevent the firing pin from striking a cap carried by said cap supporting member when the fuse is in an unarmed condition, and to yield in a direction parallel with the axis of the firing pin upon movement of said plunger relative to said firing pin; and a wall carried by said firing pin and adapted to be engaged by said stop after it has yielded, as aforesaid, to thereby lock said firing pin and plunger together and arm the fuse.

7 In a percussion fuse, a hollow casing; a cap supporting member carried by said casing; a plunger located within and movable longitudinally of said casing and having a longitudinally extending passage, and a chamber at its inner end of greater diameter than and with which said passage communicates; a firing pin located within the passage in said plunger; a combined safety and locking member held in place within the chamber aforesaid and having a plurality of yieldable stops adapted to engage the forward end of said firing pin to thereby prevent the same from striking a cap car ried by said cap supporting member when the fuse is in an unarmed condition, and to yield upon rearward movement of said plunger; and a wall carried by said firing pin and with which said stops engage after they have yielded, as aforesaid, to thereby lock said firing pin and plunger together and arm the fuse.

8. In a percussion fuse, a hollow casing;

a. cap supporting member carried by saidcasing; a plunger located within and mow able longitudinally of said casing and having a longitudinally extending passage, and a chamber at its inner end of greater diameter than and with which said passage communicates; a firing pin located within the passage in said plunger, and the rear end of which engages the end wall of said casing so that said plunger may move rearward relative to said firing pin; a yieldable combined safety and locking member located within said chamber and adapted to prevent the firing pin from striking a cap carried by said cap supporting member when the fuse is in an unarmed condition, and to yield upon rearward movement of said plunger; and means carried by said firing pin and engaged by said combined safety and locking member after said plunger has moved rearwardly, as aforesaid, to thereby lock said firing pin and plunger pin together and arm the fuse.

In testimony whereof I have signed my name to this specification this 2nd day of October, 1917.

DAVID J. CARTWRIGHT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0.? 

